scholarly journals Thermal comfort models of venue in hot and humid subtropical regions

2021 ◽  
Vol 25 (6 Part A) ◽  
pp. 4225-4231
Author(s):  
Xiaodan Huang ◽  
Qingyuan Zhang ◽  
Xiaoli Ma
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Sensation ◽  
Evaluation Model ◽  
Least Square Method ◽  
Least Square ◽  
Predicted Mean Vote ◽  
Wet Bulb Globe Temperature ◽  
Globe Temperature ◽  
The Relationship

In order to improve the design effect of venues, this paper establishes the evaluation model of indoor thermal comfort for the humid and hot subtropical areas, which provides theoretical reference for venue design. This paper investigates the thermal sensation of basketball players by questionnaire, analyzes the relation-ship between thermal sensation vote and standard effective temperature, predicted mean vote, and wet bulb globe temperature, and develops an index called predicted thermal sensation by using the least square method. The relationship between outdoor air temperature and indoor working temperature under neutral conditions is obtained by measuring data. The results show that the correlation between thermal sensation vote and air temperature is the strongest, R2 is 0.753, while the relationship between thermal sensation vote and air speed is weak, R2 is 0.012. Thermal sensation vote and set, predicted mean vote and wet bulb globe temperature are not suitable for athletes in the field environment.

scholarly journals Thermal comfort findings: Scenario at Malaysian automotive industry

2013 ◽  
Vol 17 (2) ◽  
pp. 387-396 ◽  
Author(s):  
Ahmad Ismail ◽  
Kumar Karagaratnan ◽  
Kumaran Kadirgama
Keyword(s):  
Thermal Comfort ◽  
Automotive Industry ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Human Subjects ◽  
Demographic Data ◽  
Working Environment ◽  
Paint Shop ◽  
Wet Bulb Globe Temperature ◽  
Globe Temperature

This paper discusses the findings of thermal comfort assessment at Malaysian automotive industry. Nine critical workstations were chosen as subjects for the study in order to determine the thermal comfort among workers at Malaysian automotive industry. The human subjects for the study comprises of the operators from tire receiving, dashboard assembly, drum tester, body assembly, seat assembly, door check assembly, stamping workstation, engine sub assembly and paint shop of the factory. The environmental factors such as Wet Bulb Globe Temperature (WBGT), relative humidity, air velocity, illuminance were measured using BABUC A apparatus and Thermal Comfort Measurement equipment. Through questionnaire survey, the demographic data of subjects and their perceptions on thermal comfort at each workstation were assessed based on ISO Standard 7730 and thermal sensation scale using Predicted Mean Vote (PMV). Then, Predicted Percentage of Dissatisfied (PPD) is used to estimate the thermal satisfaction of occupants. The results indicated that most of the workstations of the automotive industry are considered as uncomfortable. Tire receiving station is considered having better working environment compared to other stations with lowest PMV index of 1.09 to 1.41 and PPD of 46%. Meanwhile, the engine sub assembly station and paint shop of assembly are considered the worst thermal environment with the PMV index values ranging between 2.1 to 2.9 and PPD values of 81% to 99%. Therefore, these two workstations are considered not comfortable because the thermal sensation scale is warm and almost hot.

scholarly journals The Impact of Air Well Geometry in a Malaysian Single Storey Terraced House

2019 ◽  
Vol 11 (20) ◽  
pp. 5730 ◽  
Author(s):  
Pau Chung Leng ◽  
Mohd Hamdan Ahmad ◽  
Dilshan Remaz Ossen ◽  
Gabriel H.T. Ling ◽  
Samsiah Abdullah ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Natural Ventilation ◽  
Heat Dissipation ◽  
Air Velocity ◽  
Wet Bulb Globe Temperature ◽  
Ventilation Technique ◽  
Ventilation Performance ◽  
Globe Temperature ◽  
The Impact

In Malaysia, terraced housing hardly provides thermal comfort to the occupants. More often than not, mechanical cooling, which is an energy consuming component, contributes to outdoor heat dissipation that leads to an urban heat island effect. Alternatively, encouraging natural ventilation can eliminate heat from the indoor environment. Unfortunately, with static outdoor air conditioning and lack of windows in terraced houses, the conventional ventilation technique does not work well, even for houses with an air well. Hence, this research investigated ways to maximize natural ventilation in terraced housing by exploring the air well configurations. By adopting an existing single storey terraced house with an air well, located in Kuching, Sarawak, the existing indoor environmental conditions and thermal performance were investigated and monitored using scientific equipment, namely HOBO U12 air temperature and air humidity, the HOBO U12 anemometer and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter. For this parametric study, the DesignBuilder software was utilized. The field study illustrated that there is a need to improve indoor thermal comfort. Thus, the study further proposes improvement strategies to the existing case study house. The proposition was to turn the existing air well into a solar chimney taking into account advantages of constant and available solar radiation for stack ventilation. The results suggest that the enhanced air well was able to improve the indoor room air velocity and reduce air temperature. The enhanced air well with 3.5 m height, 1.0 m air gap width, 2.0 m length was able to induce higher air velocity. During the highest air temperature hour, the indoor air velocity in existing test room increased from 0.02 m/s in the existing condition to 0.29 m/s in the hottest day with 2.06 °C air temperature reduction. The findings revealed that the proposed air well could enhance the thermal and ventilation performance under the Malaysia tropical climate.

scholarly journals Analysis of Thermal Comfort in a Single-Family House in Poland

2020 ◽  
Vol 16 (2) ◽  
pp. 396-404
Author(s):  
Natalia Krawczyk ◽  
Sylwia Surmańska
Keyword(s):  
Relative Humidity ◽  
Thermal Comfort ◽  
Thermal Sensation ◽  
Single Family ◽  
Predicted Mean Vote ◽  
Adopted Model ◽  
Family Building ◽  
Thermal Preferences ◽  
The Relationship ◽  
Family House

AbstractThe article presents test research on thermal sensations, thermal preferences, as well as general thermal sensations in a single-family building. Graphs were drawn to determine the frequency of answers chosen by the respondents and the relationship between temperature and thermal sensations, as well as the influence of relative humidity on thermal sensations. A comparison was also made between the average thermal sensation vote and the PMV index, which determines the ‘predicted mean vote’ - estimated by the Fanger model. The aim of the study was to compare the actual feelings of the respondents with standard guidelines. As a result of this analysis it was found that the thermal sensations of the respondents do not comply with the adopted model included in the standard.

scholarly journals Thermal Performance of Single-Story Air-Welled Terraced House in Malaysia: A Field Measurement Approach

2020 ◽  
Vol 13 (1) ◽  
pp. 201
Author(s):  
Pau Chung Leng ◽  
Gabriel Hoh Teck Ling ◽  
Mohd Hamdan Ahmad ◽  
Dilshan Remaz Ossen ◽  
Eeydzah Aminudin ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Thermal Performance ◽  
Field Measurement ◽  
Natural Ventilation ◽  
Residential Buildings ◽  
Wet Bulb Globe Temperature ◽  
Natural Lighting ◽  
Ventilation Performance ◽  
Globe Temperature

The provision requirement of 10% openings of the total floor area stated in the Uniform Building By-Law 1984 Malaysia is essential for natural lighting and ventilation purposes. However, focusing on natural ventilation, the effectiveness of thermal performance in landed residential buildings has never been empirically measured and proven, as most of the research emphasized simulation modeling lacking sufficient empirical validation. Therefore, this paper drawing on field measurement investigates natural ventilation performance in terraced housing with an air-well system. The key concern as to what extent the current air-well system serving as a ventilator is effective to provide better thermal performance is to be addressed. By adopting an existing single-story air-welled terrace house, indoor environmental conditions and thermal performance were monitored and measured using HOBO U12 air temperature and humidity, the HOBO U12 anemometer, and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter for a six-month duration. The results show that the air temperature of the air well ranged from 27.48 °C to 30.92 °C, with a mean relative humidity of 72.67% to 79.25%. The mean air temperature for a test room (single-sided ventilation room) ranged from 28.04 °C to 30.92 °C, with a relative humidity of 70.16% to 76.00%. These empirical findings are of importance, offering novel policy insights and suggestions. Since the minimum provision of 10% openings has been revealed to be less effective to provide desirable thermal performance and comfort, mandatory compliance with and the necessity of the bylaw requirement should be revisited.

Approximation of the Kinematics of Foot Joints by Using Passive Elastic Characteristics of Joint

2007 ◽  
Vol 342-343 ◽  
pp. 621-624
Author(s):  
Hyeon Ki Choi ◽  
Si Yeol Kim ◽  
Won Hak Cho
Keyword(s):  
Joint Angle ◽  
Reaction Force ◽  
Force Plate ◽  
Least Square Method ◽  
Least Square ◽  
Biomechanical Analysis ◽  
Clinical Evaluations ◽  
Foot Joints ◽  
The Relationship ◽  
Elastic Characteristics

We investigated the relationship between kinematic and kinetic characteristics of foot joints resisting ground reaction force (GRF). Passive elastic characteristics of joint were obtained from the experiment using three cameras and one force plate. The relationship between joint angle and moment was mathematically modeled by using least square method. The calculated ranges of motion were 7o for TM joint, 4o for TT joint and 20o for MP joint. With the model that relates joint angle and plantar pressure, we could get the kinematic data of the joints which are not available from conventional motion analysis. The model can be used not only for biomechanical analysis which simulates gait but also for the clinical evaluations.

Parameters Identification for Nonlinear Duffing System Based on Wavelet Transformation

2013 ◽  
Vol 357-360 ◽  
pp. 1524-1530
Author(s):  
Shi Zhou ◽  
Dong Mei Huang ◽  
Wei Xin Ren ◽  
Qiong Li Wang
Keyword(s):  
Forced Vibration ◽  
Wavelet Transformation ◽  
Recognition Accuracy ◽  
Vibration Signal ◽  
Least Square Method ◽  
Least Square ◽  
Instantaneous Amplitude ◽  
Approximate Analytical Expression ◽  
Duffing System ◽  
The Relationship

Continuous wavelet transformation is made to identify the parameters of damped harmonic forced vibration Duffing system. With the aid of conversion relationship between the scale and frequency, the solution of nonlinear Duffing equation is adopted by average method, which gained approximate analytical expression for instantaneous amplitude and instantaneous frequency of the system. The nonlinear stiffness coefficient and natural frequency can be gained by least square method and the relationship between recognition accuracy and parameter selection are summarized in the article. Parameter identification method of harmonic forced vibration system is proposed in this paper. Studying the wavelet ridge and corresponding scale by segments to filter out the affects of the simple harmonic motion, to extract systems free vibration signal and to achieve the goal of identifying system parameters.

scholarly journals An Interactive Task Conditioning System Featuring Personal Comfort Models and Non-Intrusive Sensing Techniques: A Field Study in Shanghai

Technologies ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 90
Author(s):  
Siliang Lu ◽  
Erica Cochran Hameen
Keyword(s):  
Thermal Comfort ◽  
Field Study ◽  
Air Temperature ◽  
Indoor Air ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
New Paradigm ◽  
Dynamic Task ◽  
Current Task ◽  
Open Plan

Heating, ventilation and air-conditioning (HVAC) systems play a key role in shaping office environments. However, open-plan office buildings nowadays are also faced with problems like unnecessary energy waste and an unsatisfactory shared indoor thermal environment. Therefore, it is significant to develop a new paradigm of an HVAC system framework so that everyone could work under their preferred thermal environment and the system can achieve higher energy efficiency such as task ambient conditioning system (TAC). However, current task conditioning systems are not responsive to personal thermal comfort dynamically. Hence, this research aims to develop a dynamic task conditioning system featuring personal thermal comfort models with machine learning and the wireless non-intrusive sensing system. In order to evaluate the proposed task conditioning system performance, a field study was conducted in a shared office space in Shanghai from July to August. As a result, personal thermal comfort models with indoor air temperature, relative humidity and cheek (side face) skin temperature have better performances than baseline models with indoor air temperature only. Moreover, compared to personal thermal satisfaction predictions, 90% of subjects have better performances in thermal sensation predictions. Therefore, personal thermal comfort models could be further implemented into the task conditioning control of TAC systems.

scholarly journals A Study on the Relationship between Earnings Quality and Capital Cost-Takes the China Listed Companies as a Sample

2021 ◽  
pp. 48-56
Author(s):  
Chih-Yi Hsiao ◽  
Hui-Hui Kuang ◽  
Hui-Ling Li ◽  
Jia-Li Liu
Keyword(s):  
Earnings Management ◽  
Earnings Quality ◽  
Least Square Method ◽  
Listed Companies ◽  
Capital Cost ◽  
Least Square ◽  
Accounting System ◽  
Ordinary Least Square ◽  
Research Findings ◽  
The Relationship

The phenomenon of false financial statements still exists. However, in addition to the risk of being punished, what kind of price do companies have to pay? In recent decades, with China's rapid progress in economic, the relevant accounting system and corporate governance standards are actively improving, and the earnings quality is improving. This paper takes China's listed companies from 2015 to 2019 as samples, and adopts quantile regression supplemented by ordinary least square method to explore the relationship between earnings quality and capital cost. The research findings show that the higher the earnings management, the higher the capital cost, especially for the company with low capital cost. Nevertheless, for the extremely company with high capital cost, earnings management can reduce the capital cost. The research results can provide the focus of regulators of listed companies and reference for the revision of relevant accounting system.

scholarly journals Assessing The Thermal Comfort Conditions In Open Spaces: A Transversal Field Survey On The University Campus In India

2021 ◽  
Vol 8 (3) ◽  
pp. 77-92
Author(s):  
Pardeep Kumar ◽  
Amit Sharma
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Arid Regions ◽  
Thermal Sensation ◽  
Probit Analysis ◽  
Outdoor Thermal Comfort ◽  
Cold Weather ◽  
Open Spaces ◽  
Physiological Equivalent Temperature ◽  
Preferred Temperature

Outdoor thermal comfort (OTC) promotes the usage frequency of public places, recreational activities, and people's wellbeing. Despite the increased interest in OTC research in the past decade, less attention has been paid to OTC research in cold weather, especially in arid regions. The present study investigates the OTC conditions in open spaces at the campus area in the arid region. The study was conducted by using subjective surveys(questionnaire) and onsite monitoring (microclimate parameters). The study was conducted at the Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Haryana-India campus during the cold season of 2019. The timings of surveys were between 9:00 and 17:00 hours. The authors processed the 185 valid questionnaire responses of the respondents to analyze OTC conditions. Only 8.6% of the respondents marked their perceived sensation "Neutral." Regression analysis was applied between respondents' thermal sensations and microclimate parameters to develop the empirical thermal sensation model. The air temperature was the most dominant parameter affecting the sensations of the respondents. The empirical model indicated that by increasing air temperature, relative humidity, and solar radiation, the thermal sensations also increased while wind speed had an opposite effect. Physiological equivalent temperature (PET) was applied for assessing the OTC conditions; the neutral PET range was found to be 18.42-25.37°C with a neutral temperature of 21.89°C. The preferred temperature was 21.99 °C by applying Probit analysis. The study's findings could provide valuable information in designing and planning outdoor spaces for educational institutions in India's arid regions

scholarly journals The Evaluation of Outdoor Thermal Sensation and Outdoor Energy Efficiency of a Commercial Pedestrianized Zone

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1324 ◽  
Author(s):  
Xuan Ma ◽  
Hiroatsu Fukuda ◽  
Dian Zhou ◽  
Mengying Wang
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Open Space ◽  
Thermal Sensation ◽  
Heat Island ◽  
Physiological Equivalent Temperature ◽  
Winter Climate ◽  
Coverage Ratio ◽  
Urban Heat ◽  
The Relationship

The growth of the scale of cities intensifies urban heat island (UHI) by obstructing the wind and building more radiation at pedestrian level, thus leading to an energy consumption. Commercial pedestrianized-zones cannot only become symbols of cities but also an important factor increasing local economic income. This study conducts on-site measurement and numerical simulation to evaluate the cooling energy efficiency of different parameters (building, vegetation, pavement material) in Fo Shan city, which locates in hot-summer and warm-winter climate region of China. Also, calculations are done to evaluate the index physiological equivalent temperature (PET) for understanding thermal sensation at a pedestrian level (1.5 m). To evaluate different impacts of this zone renewal on the environment and choose the most energy-saving method, it is easy for us to utilize the linear regression for understanding the relationship between coverage ratio of trees (TCR) and thermal comfort in canyon space, which shows that ∆PET = 0.1703 × TCR + 0.2444 with a most important R2 value of 0.9836, for TCR increases from 12.5% to 22%. In open space, also increasing coverage ratio of trees (TCR) can effectively improve humans’ thermal comfort, which shows that ∆PET = 0.2644 × TCR + 0.3955 with a most important R2 value of 0.8892.

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